qemu/include/hw/virtio/virtio-iommu.h
Jean-Philippe Brucker 448179e33e virtio-iommu: Default to bypass during boot
Currently the virtio-iommu device must be programmed before it allows
DMA from any PCI device. This can make the VM entirely unusable when a
virtio-iommu driver isn't present, for example in a bootloader that
loads the OS from storage.

Similarly to the other vIOMMU implementations, default to DMA bypassing
the IOMMU during boot. Add a "boot-bypass" property, defaulting to true,
that lets users change this behavior.

Replace the VIRTIO_IOMMU_F_BYPASS feature, which didn't support bypass
before feature negotiation, with VIRTIO_IOMMU_F_BYPASS_CONFIG.

We add the bypass field to the migration stream without introducing
subsections, based on the assumption that this virtio-iommu device isn't
being used in production enough to require cross-version migration at
the moment (all previous version required workarounds since they didn't
support ACPI and boot-bypass).

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Message-Id: <20220214124356.872985-3-jean-philippe@linaro.org>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-03-06 05:08:23 -05:00

65 lines
1.8 KiB
C

/*
* virtio-iommu device
*
* Copyright (c) 2020 Red Hat, Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2 or later, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef QEMU_VIRTIO_IOMMU_H
#define QEMU_VIRTIO_IOMMU_H
#include "standard-headers/linux/virtio_iommu.h"
#include "hw/virtio/virtio.h"
#include "hw/pci/pci.h"
#include "qom/object.h"
#define TYPE_VIRTIO_IOMMU "virtio-iommu-device"
#define TYPE_VIRTIO_IOMMU_PCI "virtio-iommu-pci"
OBJECT_DECLARE_SIMPLE_TYPE(VirtIOIOMMU, VIRTIO_IOMMU)
#define TYPE_VIRTIO_IOMMU_MEMORY_REGION "virtio-iommu-memory-region"
typedef struct IOMMUDevice {
void *viommu;
PCIBus *bus;
int devfn;
IOMMUMemoryRegion iommu_mr;
AddressSpace as;
} IOMMUDevice;
typedef struct IOMMUPciBus {
PCIBus *bus;
IOMMUDevice *pbdev[]; /* Parent array is sparse, so dynamically alloc */
} IOMMUPciBus;
struct VirtIOIOMMU {
VirtIODevice parent_obj;
VirtQueue *req_vq;
VirtQueue *event_vq;
struct virtio_iommu_config config;
uint64_t features;
GHashTable *as_by_busptr;
IOMMUPciBus *iommu_pcibus_by_bus_num[PCI_BUS_MAX];
PCIBus *primary_bus;
ReservedRegion *reserved_regions;
uint32_t nb_reserved_regions;
GTree *domains;
QemuMutex mutex;
GTree *endpoints;
bool boot_bypass;
};
#endif